Frequency response of HD interface

[riprowan]

Hi all - sorry if this question has already been answered elsewhere, but I could not find an answer.

What is the usable / real-world frequency response of the Avid 16 x 16 192 (HD) converter box running at 96 and/or 192 KHz? I read the published specs which advise it is 20-20KHz but I'm wondering what are the actual limits? Is there a frequency response curve published somewhere?

TIA

[JFreak]

I think it's capped at 20k no matter what sample rate is used. I might be wrong about this, though...

[riprowan]

Thanks for the reply JFreak.

I'm looking for something more than anecdote. Anyone got data?

[JFreak]

http://akmedia.digidesign.com/produc...-I_O_13253.pdf

Frequency Response: +/- 0.05dB between 20Hz -- 20kHz

It doesn't say whether it's capped or not, but doesn't promise linearity outside 20-20

[browniespeaks]

its not capped as i can produce freq's below and above 20hz easy. i would imagine its not linear but should be pretty easy to measure for your unit outside 20/20. Best guess is conformity takes a hit outside spec.

[riprowan]

Thanks for the replies.

I'm not looking for the published spec. I have that. I'm looking for actual measurement results.

Browniespeaks, I would test it if I could, and save myself the trouble. I have no gear with which to test the converters.

[riprowan]

To be clear, I'm primarily concerned about the A/D converters.

[riprowan]

Bump

Sent from my HTC_Amaze_4G using Tapatalk

[Bill Denton]

Originally Posted by riprowan

To be clear, I'm primarily concerned about the A/D converters.

Just out of curiosity, why?

You're talking about frequencies outside the range of human hearing, and if some harmonics come into play they're probably washed out by the "weak link" in your audio chain.

BTW: "I want to know X because ..." esoteric questions tend to get more responses than do just a question with with no explanation...

[riprowan]

Bill, I am always having to argue/defend/explain digital audio concepts pretty much everywhere I go. So, having actual data would be very helpful when discussing these with clients.

Apple is moving towards supporting 24/96 or 24/192 audio. Now, I think this is bunk. I personally cannot hear the difference with hypersonic sampling rates. However, if Apple does it, we'll have to support it, regardless of our beliefs or opinions. And we will need to be able to talk intelligently about it, with actual data and science to dispel the myth and opinion that runs rampant.

If converters are, for example, capped at 20Khz, then we need to know that. Or if different filters are employed at higher sampling rates, then that becomes relevant to the discussion.

Now, this is pretty interesting: I can put my hands easily on frequency response curves for a dozen tape machines that have been out of production for 20 years or more, but none exist for the world's foremost digital system?

Puzzling.

Sent from my HTC_Amaze_4G using Tapatalk